Even where bookings are made offline, travellers frequently use digital tools to inform their purchases. Statista says digital travel sales will reach $818bn by 2020 while Travel Technology Europe forecasts that 58% of travel industry businesses will raise their spend on technology in 2017.

Against this backdrop, travel tech is evolving at pace, with entrepreneurs targeting ever-narower niches in each sector of the industry. Funding is following them, with the example of AirBnB, now valued more highly than hotel groups such as InterContinental Hotels and Hyatt, exciting investors in the potential of innovative start-ups. Here are just seven companies to watch.

Founded in 2015 by Kasper Middelkoop and Kristian Valk, Hotelchamp offers smart technology for hoteliers aiming to boost direct revenue and build engagement with guests in the face of the threat posed by the online travel agents (OTAs).

The company offers a suite of conversion tools powered by artificial intelligence and machine learning technologies to incentivise online customers, helping hotels to secure greater control of the relationship and to become are less dependent on third parties.

Hotelchamp has grown in two years to a team of more than 50 employees and boasts clients including The Mandeville Hotel in London, De L’Europe in Amsterdam and Hotel Palazzo Versace in Dubai. The company has raised $4.67m of funding so far and is clocking up industry awards.

TravelPerk is a free travel booking and management platform specifically designed for business travel. It delivers tools such as centralised invoicing, simplified itinerary emails and expenses integration to deliver a seamless service to users.

The company was launched in 2015 by founders Avi Meir (who sold his previous startup Hotel Ninjas to Booking.com), Javier Suarez and Ron Levin. TravelPerk has so far raised $8.5m - in May it won the Scale Startup Competition at the TNW Conference in Amsterdam.